Description

Introduction

The burst out of Diabetes mellitus over the past 30 years has transformed

the disease into a major cause of morbidity and mortality from the simple the tag of

a mild disorder of elderly. In countries like India where major population belong

to low- and middle-income group, the complete society is all the time more

affected by the disease (Whiting et al., 2011). Diabetes mellitus is a chronic

condition of multifactorial hyperglycemia with or without excretion of glucose

through urine. This deadly disease is known to the mankind since pre-historic era.

The etiologies for the rise in blood glucose range from autoimmune destruction of

pancreatic beta cell to idiopathic. The key pathophysiology behind the

hyperglycemia is the deficiency of insulin or defective response to insulin by

tissues. The metabolic alterations in diabetes mellitus over years infuriate the

functioning of various organs like heart, brain, kidney, retina, lens, vascular

system, peripheral nerves and often compromise the quality and longevity of life

(American Diabetes Association, 2010).

Diabetes mellitus, which was previously considered as single disease, now

recognized as a group of disorders and encompasses several types. The most

important and common classes of diabetes mellitus are type 1 and type 2. In this

Type 1 commonly turns out due to absolute or relative deficiency in insulin

secretion as the pancreatic cells are defective. Type 2 diabetes mellitus is a nonautoimmune

disease characterized by an elevation in the blood glucose level by a

relative deficiency in insulin secretion or insulin resistance (American Diabetes

Association, 2015).

1.1 DISARRANGEMENT OF CIRCADIAN RHYTHM - A MAJOR RISK

FACTOR FOR TYPE 2 DIABETES MELLITUS

Circadian clocks are endogenous oscillators which regulate daily rhythms in

normal physiology, metabolism and behavior. In mammals, the suprachiasmatic

nucleus (SCN) of hypothalamus is the area where the circadian clock is located,